Role of multisegmental nerve ultrasound in the diagnosis of leprosy neuropathy.

INTRODUCTION/AIMS: Leprosy is the most common treatable peripheral neuropathy worldwide. The detection of peripheral nerve impairment is essential for its diagnosis and treatment, in order to prevent stigmatizing deformities and disabilities. This study was performed to identify neural thickening through multisegmental ultrasound (US). METHODS: We assessed US measurements of cross-sectional areas (CSAs) of ulnar, median and tibial nerves at two points (in the osteofibrous tunnel and proximal to the tunnel), and also of the common fibular nerve at the fibular head level in 53 leprosy patients (LP), and compared with those of 53 healthy volunteers (HV), as well as among different clinical forms of leprosy. RESULTS: US evaluation detected neural thickening in 71.1% (38/53) of LP and a mean number of 3.6 enlarged nerves per patient. The ulnar and tibial were the most frequently affected nerves. All nerves showed significantly higher measurements in LP compared with HV, and also greater asymmetry, with significantly higher values for ulnar and tibial nerves. We found significant CSAs differences between tunnel and pre-tunnel points for ulnar and tibial nerves, with maximum values proximal to the tunnel. All clinical forms of leprosy evaluated showed neural enlargement through US. DISCUSSION: Our findings support the role of multisegmental US as a useful method for diagnosing leprosy neuropathy, revealing that asymmetry, regional and non-uniform thickening are characteristics of the disease. Furthermore, we observed that neural involvement is common in different clinical forms of leprosy, reinforcing the importance of including US evaluation of peripheral nerves in the investigation of all leprosy patients.

Shear wave elastography is a valuable tool for diagnosing and grading carpal tunnel syndrome.

OBJECTIVE: To quantify the shear velocity and stiffness of the median nerve (MN) with shear wave elastography (SWE) at the carpal tunnel entrance and determine whether SWE is useful for diagnosing and staging carpal tunnel syndrome (CTS). MATERIALS AND METHODS: The study included 58 patients (79 wrists) with clinical and electroneuromyographic diagnoses of CTS and 55 healthy controls (63 wrists). MN shear velocity and stiffness were measured by SWE on the axial plane in both groups. The differences between CTS patients and controls and between different grades of CTS based on electrodiagnostic tests were studied using Student's t test and ANOVA with ROC analysis. RESULTS: The mean MN shear velocity and stiffness were significantly greater in CTS patients (2.5 ± 0.37 m/s and 19.4 ± 5.8 kPa) than in controls (1.91 ± 0.24 m/s and 11.1 ± 3.0 kPa) (p < 0.001) and greater in the severe CTS group (2.69 ± 0.39 m/s and 22.4 ± 7.1 kPa) than in the mild CTS group (2.37 ± 0.35 m/s and 17.3 ± 4,8 kPa). The cutoff value for the shear velocity was 2.13 m/s, with 86% and 82% sensitivity and specificity, respectively, and the cutoff value for stiffness was 13.6 kPa, with 87% and 82% sensitivity and specificity. CONCLUSION: MN shear velocity and stiffness are significantly higher in CTS patients. SWE can be used to diagnose CTS and distinguish between patients with mild and severe disease.

"Million dollar nerve" magnetic resonance neurography: first normal and pathological findings.

OBJECTIVES: To evaluate prospectively the feasibility of magnetic resonance neurography (MRN) in identifying the anatomical characteristics of thenar muscular branch (TMB) of the median nerve, also known as the "million dollar nerve," in patients and controls. METHODS: Thirteen patients affected by carpal tunnel syndrome (CTS) and four healthy controls had their hands scanned on a 3-T MR imaging scanner for TMB visualization. Median nerve anatomical variations were classified into four groups according to Poisel's classification system modified by Lanz. TMB signal intensity and diameter were assessed for the diagnosis of neuropathy. RESULTS: TMB was successfully identified in all patients and subjects by using MRN. The most suitable pulse sequences to identify and measure nerve diameter were 3D DW-PSIF and T2-FS-TSE. The axial oblique and sagittal oblique planes are complementary in demonstrating its entire course. TMB had mostly an extraligamentous course with radial side origin (93.8%, each). All patients experienced increased T2 signal intensity (p < 0.001) and thickened nerves. Mean TMB diameters were 1.27 ± 0.21 mm (range, 1.02-1.74 mm) and 0.87 ± 0.16 mm (0.73-1.08 mm) (p = 0.008) in the patient and control groups, respectively. CONCLUSION: MRN is a reliable imaging technique for identification and anatomical characterization of TMB in patients affected by CTS. This innovative imaging workup may therefore be included in the preoperative evaluation of patients scheduled for carpal tunnel release, especially in CTS with TMB involvement or even in isolated TMB neuropathy. KEY POINTS: • Magnetic resonance neurography allows precise visualization of the thenar muscular branch of the median nerve. • Thenar muscular branch anatomical variations can be correctly identified. • Preoperative scanning can contribute to reducing the risk of iatrogenic injuries during carpal tunnel release, especially in carpal tunnel syndrome with thenar muscular branch involvement or even in isolated thenar muscular branch neuropathy.

Functional results after carpal tunnel release in mucopolysaccharidosis.

BACKGROUND: Mucopolysaccharidosis consists of a group of diseases caused by the deficiency of lysosomal enzymes, which may lead to the compression of the median nerve in the carpal tunnel due to the accumulation of glycosaminoglycan, resulting in the hand disability. The study purpose is to present functional results of carpal tunnel release in mucopolysaccharidosis patients. Patients were selected from an enzyme replacement group in the Department of Pediatric Neurology. The legal guardians of the patients were informed about the likely functional change of the hands induced by compression of the median nerve. Clinical evaluation was performed in those patients who received their legal guardians' consent to participate and was included inspection, assessment of functional level, wrinkle test and the digital pinch function to manipulate small and large objects. Ultrasound and electromyography were performed to confirm the clinical median nerve compression. Bilateral extended opening technique was performed to access the carpal tunnel and analyze the anatomic findings of the median nerve and the flexed tendons of the fingers. After the surgical release of the carpal tunnel, the clinical evaluation was repeated. Subjective observations of the legal guardians were also considered. RESULTS: Seven patients underwent bilateral surgical opening of the carpal tunnel; six boys, mean age of 9.5 (5 to 13), five of them presenting Type II mucopolysaccharidosis, 1 Type I and 1 Type VI. The average follow-up was 12 months (10-13 months). The functional results observed included the improvement in the handling of small and large objects in all children who underwent decompression of the median nerve. The comparison between the pre-operative and post-operative functional levels revealed that 2 patients evolved from Level II to IV, 3 from Level III to IV, 1 from Level IV to V and 1 patient remained in Level III. Tenosynovitis around the flexor tendons and severe compression of the median nerve in the fourteen carpal tunnels were observed during the surgical procedure. In 6 wrists, partial tenosynovitis was performed. CONCLUSIONS: Despite the improvement in the overall function of the children' hands, we cannot conclude that only surgery was responsible for the benefit. Better designed studies are required.

Does Patient Sex Affect Ultrasound Cutoff Values for Severity Grading of Carpal Tunnel Syndrome?

PURPOSE: A growing body of evidence supports ultrasound (US) as an alternative first-line confirmatory test for carpal tunnel syndrome (CTS). Recent studies have demonstrated a correlation of US cross-sectional area with electrodiagnostic (EDX)-determined severity; however, it is unclear whether patient sex affects the cutoff values used for determining severity. The purpose of this study was to determine if patient sex affects US graded severity when using EDX as the reference standard. METHODS: A cohort of 367 women and 46 men, aged 18-90 years, from 1 orthopedic hand surgeon's practice underwent EDX and US. Distal motor latency and distal sensory latency of the median nerve were recorded. Severity was classified using a modified Bland severity scale. The US measurements of the cross-sectional area of the median nerve at the wrist crease were acquired by a fellowship-trained hand surgeon. Separate receiver operator characteristic curve analyses of the male and female groups were performed for US cutoff values. RESULTS: The cutoff value in both the female (F) and male (M) patients was 11 mm2 for mild (area under the curve = 0.76 F; 0.78 M), 12 mm2 for moderate (area under the curve = 0.75 F; 0.73 M), and 13 mm2 for severe (area under the curve = 0.75 F; 0.71 M) CTS. The sensitivity of the cutoffs for mild, moderate, and severe CTS in the female and male groups was 49% and 56%, 44% and 50%, and 49% and 44%, respectively. The specificity of the cutoffs for mild, moderate, and severe CTS in the female and male groups was 75% and 79%, 74% and 82%, and 83% and 78%, respectively. CONCLUSIONS: Patient sex does not appear to have a significant impact on the determination of CTS severity graded using US cutoff values. Ultrasound can be used to grade the severity of CTS with a 75% to 85% specificity but low sensitivity. A cutoff value of 13 mm2 can be used to classify CTS as severe. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.

Correlation Nerve Conduction Studies with Findings of the Ultrasound of the Median Nerve in Patients with Carpal Tunnel Syndrome.

BACKGROUND: Ultrasonography is a diagnostic resource that serves as a complement in the evaluation of patients with carpal tunnel syndrome. The correlation of ultrasonography findings with nerve conduction studies can serve to classify new phenotypes and to evaluate therapeutic responses. OBJECTIVES: To determine the diagnostic sensitivity of ultrasound, the correlation between the diameter of the nerve (CSA) against the motor and sensitive latencies, and the capacity to differentiate the mild, moderate and severe degrees of the electrophysiological classification of carpal tunnel syndrome. METHODS: A cross-sectional study with prospective data collection was carried out. An ultrasonography system with a 15 MHz transducer was used. Nerve conduction studies of the median nerve were performed with conventional techniques. Data from the most symptomatic hand were used. Determination of the correlations of nerve diameter with motor and sensitive latencies of the median nerve was performed in four age groups: <40(n=11), 40-54 (n=47), 55-70 (n=42) y >70(n=27). RESULTS: A total of 127 patients were evaluated (average age = 58.2 years: minimum = 26; maximum = 85; SD = 13.4); 109 (85.8%) were female patients. According to the electrophysiological classification, 40 (31.5%) were mild ; 60 (47.2%) were moderate ; and 27 (21.3%) were severe . Significant differences in the area of the median nerve were found between the electrophysiological types (mild, moderate and severe; p = 0.000). The diagnostic sensitivity of ultrasonography differed for each age group. In general, the diagnostic sensitivity was high in patients with severe cases and low for mild cases. The capacity for ultrasonography to classify the degrees of electrophysiological severity was different for each age group. For patients above 70 years and in the age group of 40 to 54 years, the CSA did not differentiate the electrophysiologically moderate cases from the severe ones. CONCLUSION: There is a well-defined and significant correlation between nerve conduction studies and median nerve diameter in patients with Carpal Tunnel Syndrome. However, it shows that the exclusive use of the ultrasonographic measurement of the cross-sectional area through the inlet of the carpal tunnel would not be enough to confirm or rule out an entrapment of the median nerve through the carpal tunnel, nor to predict in every case their electrophysiological severity.

[Sensitivity and specificity of three complementary methods in the diagnosis of carpal tunnel syndrome]. / Sensibilidad y especificidad de tres métodos complementarios para el diagnóstico de síndrome de túnel carpiano.

INTRODUCTION: Currently there is no universally accepted standard of reference for the diagnosis of carpal tunnel syndrome so it is considered a «latent class¼ pathology, that is, it lacks any diagnostic tests that absolutely certain the presence of disease. METHODS: Prospective, observational and analytical study evaluating the three diagnostic methods used for carpal tunnel syndrome (clinical examination, ultrasound and electromyography). Normality values were set for each diagnostic method. RESULTS: 50 people (14 men and 36 women) were evaluated. The clinical examination showed a positive and significant correlation with the diameter of the affected median nerve (ecography) (R = 0.694, p = 0.032). The values of the under the curve area (UCA) for median nerve conduction speed (MNCS), cubital nerve conduction speed (CNCS), and distal latency (DL) by electromyography were 0.60, 0.519 and less than 0.50 respectively. This states that the diagnostic value of electromyography characteristics is bad. CONCLUSION: Our work establishes clinical examination as a good quality tool being the most sensitive method for diagnosing carpal tunnel syndrome. If there was a need for diagnostic confirmation, the ultrasound proved to be a highly satisfactory study generating less stress, pain and invasion to the patient, decreasing health expenditure and speeding up the process.

INTRODUCCIÓN: Actualmente, no existe un estándar de referencia aceptado universalmente para el diagnóstico del síndrome de túnel carpiano, por lo que se le considera una patología de «clase latente¼, es decir, que carece de alguna prueba diagnóstica que dé certeza absoluta de la presencia de la enfermedad. MÉTODOS: Estudio prospectivo, observacional y analítico en el cual se evaluaron los tres métodos diagnósticos utilizados para el síndrome de túnel carpiano (examen clínico, ecografía y electromiografía). En él, se establecieron valores de normalidad para cada método diagnóstico. RESULTADOS: Se evaluó un total de 50 personas (14 hombres y 36 mujeres). El examen clínico presentó correlación positiva y significativa con el diámetro del nervio mediano afectado (ecografía) (R = 0.694 y p = 0.032). Los valores del área bajo la curva (AUC, por sus siglas en inglés) para la velocidad de conducción del nervio mediano (VCNM), velocidad de conducción de nervio cubital (VCNC) y latencia distal motora (LDM) por electromiografía fueron de 0.60, 0.519 y. CONCLUSIÓN: < 0.50, respectivamente, lo cual determinó que el valor diagnóstico de las características por electromiografía es malo. Nuestro trabajo establece al examen clínico como una herramienta de buena calidad, siendo el método más sensible para el diagnóstico de síndrome de túnel carpiano. Si existiera la necesidad de realizar una confirmación diagnóstica, la ecografía mostró ser un estudio altamente satisfactorio, el cual genera menos estrés, dolor e invasión al paciente, disminuyendo, a su vez, el gasto de salud y agilizando el proceso.

Sensibilidad y especificidad de tres métodos complementarios para el diagnóstico de síndrome de túnel carpiano / Sensitivity and specificity of three complementary methods in the diagnosis of carpal tunnel syndrome

Resumen: Introducción: Actualmente, no existe un estándar de referencia aceptado universalmente para el diagnóstico del síndrome de túnel carpiano, por lo que se le considera una patología de «clase latente¼, es decir, que carece de alguna prueba diagnóstica que dé certeza absoluta de la presencia de la enfermedad. Métodos: Estudio prospectivo, observacional y analítico en el cual se evaluaron los tres métodos diagnósticos utilizados para el síndrome de túnel carpiano (examen clínico, ecografía y electromiografía). En él, se establecieron valores de normalidad para cada método diagnóstico. Resultados: Se evaluó un total de 50 personas (14 hombres y 36 mujeres). El examen clínico presentó correlación positiva y significativa con el diámetro del nervio mediano afectado (ecografía) (R = 0.694 y p = 0.032). Los valores del área bajo la curva (AUC, por sus siglas en inglés) para la velocidad de conducción del nervio mediano (VCNM), velocidad de conducción de nervio cubital (VCNC) y latencia distal motora (LDM) por electromiografía fueron de 0.60, 0.519 y < 0.50, respectivamente, lo cual determinó que el valor diagnóstico de las características por electromiografía es malo. Conclusión: Nuestro trabajo establece al examen clínico como una herramienta de buena calidad, siendo el método más sensible para el diagnóstico de síndrome de túnel carpiano. Si existiera la necesidad de realizar una confirmación diagnóstica, la ecografía mostró ser un estudio altamente satisfactorio, el cual genera menos estrés, dolor e invasión al paciente, disminuyendo, a su vez, el gasto de salud y agilizando el proceso.

Abstract: Introduction: Currently there is no universally accepted standard of reference for the diagnosis of carpal tunnel syndrome so it is considered a «latent class¼ pathology, that is, it lacks any diagnostic tests that absolutely certain the presence of disease. Methods: Prospective, observational and analytical study evaluating the three diagnostic methods used for carpal tunnel syndrome (clinical examination, ultrasound and electromyography). Normality values were set for each diagnostic method. Results: 50 people (14 men and 36 women) were evaluated. The clinical examination showed a positive and significant correlation with the diameter of the affected median nerve (ecography) (R = 0.694, p = 0.032). The values of the under the curve area (UCA) for median nerve conduction speed (MNCS), cubital nerve conduction speed (CNCS), and distal latency (DL) by electromyography were 0.60, 0.519 and less than 0.50 respectively. This states that the diagnostic value of electromyography characteristics is bad. Conclusion: Our work establishes clinical examination as a good quality tool being the most sensitive method for diagnosing carpal tunnel syndrome. If there was a need for diagnostic confirmation, the ultrasound proved to be a highly satisfactory study generating less stress, pain and invasion to the patient, decreasing health expenditure and speeding up the process.

Variantes anatómicas del canal carpiano y distancias de estructuras vasculares en ecografía / Anatomical variants the carpal tunnel and distances of vascular structures in ultrasound

El síndrome de canal carpiano es una patología frecuente. Si bien el diagnóstico es clínico, la ecografía cumple un rol en caso de duda diagnóstica y como apoyo a proce-dimientos intervencionales.Existen variables anatómicas y distancias de estructuras vasculares útiles de conocer antes de planear un gesto quirúrgico o de infiltración para disminuir el riesgo de lesiones secundarias, en donde la ecografía podría tener un rol.Estudiamos una muestra de 267 ecografías de muñeca con especial hincapié en va-riantes neurogénicas, vasculares o tendinosas que podrían resultar lesionadas en relación a algún procedimiento.

Carpal tunnel syndrome is a frequent pathology. Although the diagnosis is clinical, ultrasound plays a role in case of diagnostic doubt and as support and guide for inter-ventional procedures.There are anatomical variants and distances of vascular structures that may be useful to know before planning a surgical or infiltration procedure to reduce the risk of iat-rogenic injuries, where ultrasound could play a role.We studied a sample of 267 wrists ultrasounds with special emphasis on neurogenic, vascular or tendinous variants that could be injured in relation to procedures.

Sonographic Findings of the Bifid Median Nerve and Persistent Median Artery in Carpal Tunnel: A Preliminary Study in Chinese Individuals.

OBJECTIVE:: The aim of this study was to investigate the prevalence of anatomic variations of the bifid median nerve, persistent median artery and persistent median vein in Chinese individuals and their relationship with carpal tunnel syndrome. METHODS:: One hundred and sixty median nerves were examined using ultrasonography and colour Doppler ultrasonography. The location, shape, and size of the bifid median nerve, persistent median artery and persistent median vein were recorded. The cross-sectional area of the bifid median nerve (two trunks) was measured at the level of the pisiform. RESULTS:: Among the 160 wrists examined, a bifid median nerve was observed in 15 (9.4%) wrists, and a persistent median artery was observed in 12 (7.5%) wrists. These two variations either coexisted or were observed independently, and the probability of coexistence (6.3%) was higher than the probability of existing independently (bifid median nerve only 3.1%, persistent median artery only 1.3%). The cross-sectional area of the radial trunk was greater than (13 in 15, 86.7%) the cross-sectional area of the ulnaris trunk. Persistent median vein was observed in 9 wrists (5.6%). CONCLUSIONS:: The persistent median artery and bifid median nerve tend to coexist, and the persistent median vein sometimes runs parallel to the persistent median artery. Their positional relationship in carpal tunnel is uncertain, and thus, preoperative ultrasound is necessary. These three variations do not present any additional risk for the development of carpal tunnel syndrome.

Sonographic Findings of the Bifid Median Nerve and Persistent Median Artery in Carpal Tunnel: A Preliminary Study in Chinese Individuals

OBJECTIVE: The aim of this study was to investigate the prevalence of anatomic variations of the bifid median nerve, persistent median artery and persistent median vein in Chinese individuals and their relationship with carpal tunnel syndrome. METHODS: One hundred and sixty median nerves were examined using ultrasonography and colour Doppler ultrasonography. The location, shape, and size of the bifid median nerve, persistent median artery and persistent median vein were recorded. The cross-sectional area of the bifid median nerve (two trunks) was measured at the level of the pisiform. RESULTS: Among the 160 wrists examined, a bifid median nerve was observed in 15 (9.4%) wrists, and a persistent median artery was observed in 12 (7.5%) wrists. These two variations either coexisted or were observed independently, and the probability of coexistence (6.3%) was higher than the probability of existing independently (bifid median nerve only 3.1%, persistent median artery only 1.3%). The cross-sectional area of the radial trunk was greater than (13 in 15, 86.7%) the cross-sectional area of the ulnaris trunk. Persistent median vein was observed in 9 wrists (5.6%). CONCLUSIONS: The persistent median artery and bifid median nerve tend to coexist, and the persistent median vein sometimes runs parallel to the persistent median artery. Their positional relationship in carpal tunnel is uncertain, and thus, preoperative ultrasound is necessary. These three variations do not present any additional risk for the development of carpal tunnel syndrome.

Ultrasound elastography assessment of the median nerve in leprosy patients.

INTRODUCTION: We sought to compare median nerve elasticity between leprosy patients (LPs) and healthy volunteers (HVs) using ultrasound elastography (UE). METHODS: Two radiologists independently measured the strain ratio of the median nerve/flexor digitorum superficialis muscle (MN/FDSM) of 18 LP and 18 HV using real-time freehand UE. Statistical analysis included intra-class correlation coefficients (ICC) and Mann-Whitney test. RESULTS: The MN/FDSM strain ratios of the LP and HV were 2.66 ± 1.30 and 3.52 ± 0.93, respectively (P < 0.05). We observed a significantly lower MN/FDSM strain ratio in LP with reactions (types 1 and 2 cutaneous reactions associated with or without neuritis) (2.30 ± 0.91) compared with LP without reactions (3.60 ± 1.70). We found no significant differences between HV and LP without reactions. The intra- and inter-observer ICCs were 0.50 (95% confidence interval [CI], 0.11-0.72) and 0.34 (95% CI, 0.28-0.52), respectively. CONCLUSIONS: MN/FDSM strain ratios were significantly lower in LP with reactions. UE may be useful for nerve elasticity evaluation in leprosy. Muscle Nerve 56: 393-398, 2017.

Asymmetric Nerve Enlargement: A Characteristic of Leprosy Neuropathy Demonstrated by Ultrasonography.

BACKGROUND: Neurological involvement occurs throughout the leprosy clinical spectrum and is responsible for the most feared consequences of the disease. Ultrasonography (US) provides objective measurements of nerve thickening and asymmetry. We examined leprosy patients before beginning multi-drug therapy aiming to describe differences in US measurements between classification groups and between patients with and without reactions. METHODOLOGY/PRINCIPAL FINDINGS: Eleven paucibacillary (PB) and 85 multibacillary (MB) patients underwent nerve US. Twenty-seven patients had leprosy reactions (type 1, type 2 and/or acute neuritis) prior to US. The ulnar (at the cubital tunnel-Ut-and proximal to the tunnel-Upt), median (M) and common fibular (CF) nerves were scanned to measure cross-sectional areas (CSAs) in mm2 and to calculate the asymmetry indexes ΔCSA (absolute difference between right and left CSAs) and ΔUtpt (absolute difference between Upt and Ut CSAs). MB patients showed greater (p<0.05) CSAs than PB at Ut (13.88±11.4/9.53±6.14) and M (10.41±5.4/6.36±0.84). ΔCSAs and ΔUtpt were similar between PB and MB. The CSAs, ΔCSAs and ΔUtpt were similar between PB patients with reactions compared to PB patients without reactions. MB patients with reactions showed significantly greater CSAs (Upt, Ut and M), ΔCSAs (Upt and Ut) and ΔUtpt compared to MB patients without reactions. PB and MB showed similar frequencies of abnormal US measurements. Patients with reactions had higher frequency of nerve thickening and similar frequency of asymmetry to those without reactions. CONCLUSIONS/SIGNIFICANCE: This is the first study to investigate differences in nerve involvement among leprosy classification groups using US before treatment. The magnitude of thickening was greater in MB and in patients with reactions. Asymmetry indexes were greater in patients with reactions and did not significantly differ between PB and MB, demonstrating that asymmetry is a characteristic of leprosy neuropathy regardless of its classification.

New sonographic measures of peripheral nerves: a tool for the diagnosis of peripheral nerve involvement in leprosy.

To evaluate ultrasonographic (US) cross-sectional areas (CSAs) of peripheral nerves, indexes of the differences between CSAs at the same point (∆CSAs) and between tunnel (T) and pre-tunnel (PT) ulnar CSAs (∆TPTs) in leprosy patients (LPs) and healthy volunteers (HVs). Seventy-seven LPs and 49 HVs underwent bilateral US at PT and T ulnar points, as well as along the median (M) and common fibular (CF) nerves, to calculate the CSAs, ∆CSAs and ∆TPTs. The CSA values in HVs were lower than those in LPs (p < 0.0001) at the PT (5.67/9.78 mm2) and T (6.50/10.94 mm2) points, as well as at the M (5.85/8.48 mm2) and CF (8.17/14.14 mm2) nerves. The optimum CSA- receiver operating characteristic (ROC) points and sensitivities/specificities were, respectively, 6.85 mm2 and 68-85% for the PT point, 7.35 mm2 and 71-78% for the T point, 6.75 mm2 and 62-75% for the M nerve and 9.55 mm2 and 81-72% for the CF nerve. The ∆CSAs of the LPs were greater than those of the HVs at the PT point (4.02/0.85; p = 0.007), T point (3.71/0.98; p = 0.0005) and CF nerve (2.93/1.14; p = 0.015), with no difference found for the M nerve (1.41/0.95; p = 0.17). The optimum ∆CSA-ROC points, sensitivities, specificities and p-values were, respectively, 1.35, 49%, 80% and 0.003 at the PT point, 1.55, 55-85% and 0.0006 at the T point, 0.70, 58-50% and 0.73 for the M nerve and 1.25, 54-67% and 0.022 for the CF nerve. The ∆TPT in the LPs was greater than that in the HVs (4.43/1.44; p <0.0001). The optimum ∆TPT-ROC point was 2.65 (90% sensitivity/41% specificity, p < 0.0001). The ROC analysis of CSAs showed the highest specificity and sensitivity at the PT point and CF nerve, respectively. The PT and T ∆CSAs had high specificities (> 80%) and ∆TPT had the highest specificity (> 90%). New sonographic peripheral nerve measurements (∆CSAs and ∆TPT) provide an important methodological improvement in the detection of leprosy neuropathy.

[The cross-sectional area of the median nerve by sonography in the diagnosis of carpal tunnel syndrome]. / Determinación ultrasonográfica del área de corte transversal del nervio mediano en síndrome del túnel carpiano.

OBJECTIVE: To measure the median nerve cross-sectional area (MNCSA) at the carpal tunnel (CT) level by sonography (S) in a Mexican population. METHODS: A comparative cross-sectional design study with a nonprobabilistic sampling with 50 women and 50 men in good health were submitted for measuring MNCSA at the level of the CT. Other variables like sex; side and degree of daily hand activity were also studied. The analysis was made by descriptive statistics, and Mann-Whitney U or Kruskal-Wallis tests. RESULTS: The mean MNCSA was 0.063 +/- 0.015 cm(2), in women; in men it was 0.072 +/- 0.018 cm(2); the difference was significant (p < 0.004). The median MNCSA among women was 0.062 cm(2) in the right side and 0.060 cm(2) in the left (90th percentile for both hands of 0.084 cm(2)); in men, it was of 0.070 cm(2) in the right hand and of 0.069 cm(2) in the left (90th percentile for both hands of 0.097 cm(2)). The difference between women and men was significant in each side, but not between right and left hands (p = 0.21). There was no correlation between age and MNCSA on either side, or with hand activity. CONCLUSIONS: A MNCSA value of 0.1 cm(2) for men and 0.09 cm(2) for women is proposed as a standard parameter for the Mexican population.

Ultrasound evaluation of patients with carpal tunnel syndrome before and after endoscopic release of the transverse carpal ligament.

AIM: To evaluate the cross-sectional area of the median nerve using ultrasound in carpal tunnel syndrome patients before and after endoscopic intervention. MATERIAL AND METHODS: Twenty patients with carpal tunnel syndrome (15 women and five men; mean age 55 years) were prospectively evaluated. Informed consent was obtained from all participants. The study was approved by our Institutional Review Board (IRB). Median nerve cross-sectional area was evaluated at the proximal level before and at 4, 8, and 12 weeks after endoscopic release of the transverse ligament. In the present study, the median nerve cross-sectional area cut-off point was 10 mm(2). Repeated measures analysis of variance test (ANOVA) was applied to compare the reproducibility of ultrasound measurements before and after intervention. RESULTS: The mean cross-sectional area of the median nerve was 15 mm(2) (SD+/-2.1) before surgery; and 11.1 mm(2) (SD+/-3); 9.2 mm(2) (SD+/-2); and 8.6 mm(2) (SD+/-1.6) at 4, 8, and 12 weeks after surgery. Repeated measures analyses of variance were found to be statistically significant (p<0.001). CONCLUSION: The results of the present study demonstrated that there was a decrease in the cross-sectional area of the median nerve after the release of the transverse carpal ligament.